The "Alien Sector" was the name given to an area of Green Sector specifically adapted to accommodate the different atmospheric needs of 14 different species residing on the station, located between the docking bays and Red Sector. Since most of Babylon 5's residents were natural oxygen breathers, access to and from the Alien Sector was maintained through a series of airlocks, in which standard breather masks capable of being used by most races were available for use in dispensers. In a somewhat ironic twist, the residents of this area tended to refer to the larger, oxygen-rich part of the station as the "Alien Sector".